1. Field of the Invention
The present invention relates to an elastic shaft coupling having a mechanical interface on the drive side and on the power take-off side, both interfaces for connecting the shaft coupling to an adjacent machine element, in each instance, whereby the shaft coupling has at least two elastic rubber bodies placed one behind the other between the interface on the drive side and on the power take-off side, whose axial material thickness increases with an increasing radial distance from the center axis of the shaft coupling, in each instance.
2. The Prior Art
Such a shaft coupling is known from the German Offenlegungsschrift [examined patent published for public scrutiny] DE 197 14 420 A1 of the same applicant.
Elastic shaft couplings of the type stated initially serve to damp rotary vibrations in drive trains. Furthermore, they even out radial and axial offset of individual sections of the drive train, relative to one another. For example, the transmission of a ship is generally mounted in fixed manner, while the ship diesel is mounted elastically. The offset of the engine resulting from vibrations and hull deformations is compensated by means of an elastic shaft coupling that is disposed between engine and transmission. Furthermore, the elastic shaft coupling damps rotary vibrations that occur in the system.
The elastic rubber bodies of such couplings have the form of a rotation body, the rotation surface of which is approximately V-shaped. Because of this geometry, the axial material thickness of the rubber increases with an increasing radial distance from the center axis of the shaft coupling, in order to guarantee a uniform stress distribution within the rubber body, over its entire diameter.
In the selection of the coupling for the predetermined drive train, the individual torsion spring constants and mass inertia moments of the rubber bodies and their flanking disks are significant parameter values. In order to vary these, in terms of design, in the past the increase in material thicknesses of the rubber bodies was changed, as were the material-specific spring constants. However, in this connection the axial material thicknesses of the rubber bodies were always varied in identical measure, and this led to the result that the rubber bodies always appear with mirror symmetry in a mirror plane perpendicular to the center axis of the shaft coupling. Since the same material was also always provided for the two rubber bodies, this led to the result, in the final analysis, that the torsion spring constants of the individual rubber bodies were approximately identical. The amount of rubber resulting from this was accepted as being a given.